Light emitting diodes (LEDs) are attractive candidates for replacing conventional light sources such as incandescent and fluorescent lamps. LEDs have substantially higher light conversion efficiencies than incandescent lamps and longer lifetimes than both types of conventional light sources. In addition, some types of LEDs now have higher conversion efficiencies than fluorescent light sources and still higher conversion efficiencies have been demonstrated in the laboratory. Finally, LEDs require lower voltages than fluorescent lamps, and therefore, provide various power saving benefits.
Despite the advantages of using LEDs as light sources, consumer acceptance will depend largely on the adaptability of these sources into existing lighting fixtures using conventional light sources (e.g., incandescent or fluorescent lamps). LED light sources designed for direct replacement of conventional light sources could be instrumental in accelerating consumer acceptance, and thereby, revolutionize the lighting industry. Unfortunately, there exists significant challenges in designing LED light sources that directly replace existing light sources, such as the incandescent light bulb for example.